Background

Incidence of shoulder pathology ranges from 7 to 25 per 1000 visits to primary care physicians

Prevalence ranges from 7% to 27% in those less than 70 years of age and 13% to 26% in those older than 70 years of age

Repetitive or excessive contact or abrasion of the rotator cuff muscles and/or tendons due to compression between the humeral head and acromion, coracoacromial ligament and acromioclavicular joint

Risk Factors

Deconditioning

Neurological injuries

Sports involving throwing or overhead activities

Trauma

Poor ergonomics

Clinical Features

Shoulder pain causes pain along the scapula and trapezius muscle but not the neck and is worsened with forward flexion of the shoulder and the pain is often referred to the lateral shoulder and mid arm. Patients note difficultly removing their shirt or coat

Cervical pathology can radiate into the shoulder and shoulder pathology can radiate into the neck

Cervical pathology may lead to secondary shoulder disease such as frozen shoulder

Atrophy of the shoulder musculature can be associated with either C5 or C6 radiculopathy or chronic rotator cuff injury

Active shoulder range of motion limitations may be related to deltoid or rotator cuff weakness resulting from a cervical radiculopathy or disuse atrophy caused by pain.

Progresses from edema and hemorrhage to cuff fibrosis and thickening or a partial cuff tear and finally develop into full thickness tears, tendon ruptures and bony changes

Diagnosis

Differential diagnosis

Cervical disc herniation with radiculopathy

Cervical myelopathy

Cervical spondylosis

Frozen shoulder

Glenohumeral instability or osteoarthritis

Lung tumors

Nerve palsies

Shoulder impingement syndrome

Workup

X-rays of the shoulder should include anterior-posterior, lateral and axillary views

MRI is the study of choice for assessing for rotator cuff tears

MRI may detect rotator cuff tears in 34% of asymptomatic individuals and this frequency increases with age